It is known in the communications arts that voice calls can be carried by the Internet (or some other data transport network) between a pair of Internet phones or voice-enabled computers. It is also known that voice calls carried by the Internet can be interfaced by a gateway to the telephone network so that an Internet phone or a voice-enabled computer connected to the Internet can engage in a voice call with a standard telephone connected to the telephone network. Illustrative examples of such capabilities are disclosed in "Netspeak's Hot Internet Sun Product", Computer Telephony, Vol. 5, Issue 8 (August 1996), pp. 120-124, and in "Internet Hop Off", Computer Telephony, Vol. 4, Issue 3 (March 1996), pp. 10-11. It is further known that telephony features can be provided to computers or terminals on a local area network (or some other data transport network) via a feature server. An illustrative example of such capability is disclosed in U.S. Pat. No. 5,550,906. Telephony features are features that are provided to telephones and telephone calls by modern telecommunications switching systems, such as the Lucent Technologies Inc. Definity.RTM. private branch exchange. They may include, by way of example and without limitation, features such as call redirection (e.g., call forwarding, call coverage), multiple call appearances (e.g., hold, drop, transfer, conference), call center agent features (e.g., agent login, agent logout, after-work mode, etc.), call center management information features (e.g., maximum time in queue, queue length, skill-based split staffing levels, etc.), and calling party information features (e.g., position in queue, advertising-on-hold, etc.). Providing a Web-page-like interface for system management and administration of Internet-accessible systems is also known. An example thereof may be found in the router products of the Advanced Computer Communications company.
Standards have not been developed for protocols by which computers, terminals, Internet phones, and other devices--jointly referred to as clients--can interact with feature servers over the Internet and other non-telephony communications networks in order to access telephony features. Consequently, the clients and the servers must be specifically designed and configured to work with each other, typically via a proprietary protocol that includes telephony feature access commands, and they typically are unable to work with servers or clients of a different design or configuration--other manufacturers' equipment, for example. This has the serious and unfortunate consequence that the use of feature servers is limited to "closed" networks that are controlled by a single entity--e.g., a single company's local area network--that can dictate what equipment and feature-access protocol is used on the network, and that the use of feature servers is not possible on "open" networks such as the Internet.